Electrical relay



Sept 24 1935. L. E RICHMGND ELECTRI GAL RELAY Filed NOV. 1'7, 1932INVENTOR. iouz's Fz'c/zmwuZ ATTORNEYS- Patented Sept. 24, 1935 PATENTOFFICE ELECTRICAL RELAY Louis E. Richmond, Shelby, Ohio, assignor to TheAutocall Company, Shelby, Ohio, a. corporation of Ohio ApplicationNovember 1'7, 1932, Serial No. 643,064

9 Claims. (01. 200-87) The present invention relates to that type ofelectrical apparatus designed for the purpose of reproducing electricimpulses from one circuit to another. Generally, such a relay action, asit is called, has been accomplished by the mechanical movement of asolenoid or armature adapted to close the contacts of one electriccircuit, and energized by the magnetomotive force of the other electriccircuit. It is the general object and nature of my invention to providea novel form of moving element in such a combination which shall possessthe advantages of eiiiciency and facility of operation, as well as asubstantially greater durability as compared to the devices of the priorart; The more precise objects and advantages of my invention shall beenumerated and become apparent as the following description proceeds. Tothe accomplishment of the foregoing and related ends, said invention,then, consists of the means hereinafter fully described and particularlypointed out in the claims.

Fig. l is a half sectioned elevation of the relay constructed accordingto the principle of my invention and showing the moving elements innormal or de-energized position; Fig. 2 is similar to Fig. 1, but showsthe moving elements in circuit closing or energized position; Fig. 3 isa wiring diagram illustrative of a simple form of circuit in which myrelay may be used; Fig. 4 is a section plan view on relatively smallscale illustrating the direction and concentration of the lines ofmagnetic force induced between the terminals of the secondary circuit.

Heretofore electric relays have utilized a single element in the form ofa bar or rod as the mechanically moving element adapted to close thecontacts of the secondary circuit. The prominent disadvantages inherentin such a construction were that there occurred an unusually noisyoperation when the contact was initially made and an objectionablesparking due to current surges when the contact was broken. Brieflyoutlined, the principle of my invention contemplates the formation ofsuch an armature or solenoid element into a plurality of small particleswhich will be adapted to remain inmutual contact one with the other andto move against the terminal pieces with practically no noise at all, orat most a slight swishing sound; additionally, these particles areadapted to prevent excessive sparking, line surge and self induction areprevented when the contact is broken, due to the multiplicity ofcontacts, and the gradual decrease of magnetic constriction of saidcontacts during the cycle of change from magnetomotive urge togravitational urge when the magnetic force is interrupted by opening theprimary circuit.

Now referring more particularly to the annexed drawing, 1 haveundertaken to describe a form of apparatus which is considered as apractical embodiment of the above delineated principle. The numeralgenerally designates a metallic housing member which serves as amagnetic yoke as well as a supporting member for the device. An electriccoil or coils 2 are supported within the housing member I. In the topand bottom portion of the housing l are the openings 3 and 4 which areadapted to receive the closed chamber 5 which is composed of anon-conducting material such as glass. A pair of magnetically conductingbars or magnetic cores 6 and I extend through the upper and lower endsrespectively of the chamber 5. The upper terminal has its lower endenlarged or flared into the conical form des ignated by the numeral 8. Acap 9 composed of a material such as silver or copper having arelatively high co-emcient of electrical conductivity is adapted tocover the lower contacting surface of the magnetic core end 8.Alternatively, the cap 9 may be displaced by a heavy electro-platedlayer of silver or copper. The contacting portion of the magnetic core Iis in the form of a cylinder having a rounded or semi-spherical end, andis designated by the numeral i0. Similarly, a silver or copper cap orheavy electro-plate H is secured over the terminal portion H) "of thecore I and adapted to serve as a contacting surface. In the interior ofthe chamber 5 and occupying the space between the ends of the cores tand l are found a plurality of small particles l2, which, in theirpreferred form, are spherical. A washer 13 or nonmagnetic material ispositioned immediately below the cap l i and is for the pu pose ofretaining the spherical balls l2 in proper position as shown in Fig. 1when no current is passed through the magnetic energizing coil 2.Another washer composed of insulating material is threadably secured tothe threaded portion 15 of the magnetic core 6, and is for the purposeof adjustably regulating the position of the chamber 5 with respect tothe electro-magnetic coil 2. Terminal caps It and I? are attached toeach exposed ends of the cores 6 and 1 respectively. The conductingwires or cables !8 and It in turn lead from the terminal caps 5, E1.

The interior of the chamber 5 is to be pneumatically exhausted andfilled with an inert gas, or a non-conducting fluid to provide anon-oxidizing and quenching medium. The exhausting duct 20 is providedthrough the axis of the magnetic core 6, placing the interior of thechamber 5 in communication with the outside atmosphere. It iscontemplated that the duct 20 may be equally as well positioned in thecore I, or both. The provision of the duct 20 eliminates the necessityof providing an additional opening through the wall of the chamber 5,and greatly facilitates the operation of exhausting or charging theinterior of such chamber.

In the operation of the above described device, two electrical circuitsare utilized, and may be designed as a primary and secondary circuit,respectively. Now referring to the diagrammatic Fig. 3, the primarycircuit consists of a source of electric energy 2| connected to a switch22 which is adapted to intermittently open and close such circuit. Theconducting wires 23 and 24 connect the electrical source M and switch 22to the electro-magnetic coil 2. Now, the secondary circuit consists ofthe chamber 5 with its above described interior elements and theconducting wires l8 and I! leading to another source of electricalenergy 25 and an element such as an alarm signal bell 28. It is to benoted that any similar electrically motivated device, such as a signallight or code recorder may take the position of the alarm cell 2'. Whenthe primary circuit is closed, the coil 2 becomes electrically energizedand a. magnetic field is induced in the magnetic cores 6 and 7. Thismagnetic field is conducted through the terminals or cores 6 and l, andsets up a magnetic flux having a path of travel substantially asindicated by the lines 21 in Fig. 4. The balls I2 are then urged due tomagnetic energization to move from their normal position as shown inFig. 1 to their final energized position as shown in Fig. 2, whereby anelectric contactz-is' obtained between the terminals 6 and 'Lthrough theballs i2, incidentally closing the secondary circuit. Analyzing themovement of the balls l2, it is to be found that they move first fromtheirtposition in Fig. l inwardly and centrally towa'rdthe post II. Inthis position they form substantially a cone having its base on a linecoincident with the upper surface of the supporting washer l3. Themovement of the balls, which is of course very rapid and continuous withtheir initial movement, is upward, following the magnetic field towardthe bottom surface of the enlarged core portion 8. In their finalposition they are as shown in Fig. 2, defining substantially an invertedcone having its base along the bottom surface of the core end 8 and itsapex magnetically held in contact with core I. when the primary circuitis again opened and the magnetic field induced by the coil 2 isdissolved, the balls I2 in turn become slowly deenergized, permittingdissipation of secondary line surge and resume their position of Fig. 1,thereby gradually breaking the contact and opening the secondarycircuit. It should also be noted at this point that the balls I! arecomposed of a material having a substantially low magnetic retentivitysuch as iron or soft steel, and are coated with a layer of material suchas silver or copper having a relatively high co-efilcient of electricconductivity. There is sufficient retentivity in the material of theballs i2, however, so that they will not simultaneously drop to normalgravitational position, but their partial residual magnetism will tendto hold them in contacting position a fraction of a moment longer,whereby a current surge, especially if it happens to be the peak of analternating current wave will be satisfactorily dissipated. This latterfunction is of unusual advantage in alternating current installations,since the rapid opening of alternating current contacts invariablyresults in excessive sparking, whereas a slow breaking of such contactsis marked by the total absence of any destructive sparking. It shouldalso be'remarked that the lower terminal end [0 is made of across-sectional size or diameter substantially equal to twice thecross-sectional size of the balls II, this latter structural expedientis for the purpose of providing a sufiiciently large contacting surfacewhereby an adequate number of the balls I! will be retained in contactwith the lower terminal upon energization.

Inasmuch as the magnetic field induced by the coil 2 is of varyingintensity at different points, the chamber 5 is made adjustable as toits position with respect to such magnetic field. This latter expedientis attained by means of lowering or raising the threaded portion ii ofthe upper terminal G with respect to the supporting washer I.

It will thus be seen that I have provided an electric relay possessingan unusual efliciency of operation, eliminating the disadvantageous andobjectionable features of devices found in the prior art.

Other modes of applying the principle of my invention may be. employedinstead of the one explained, change beingmade as regards the mechanismherein disclosed, provided the means stated by any of the followingclaims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. In an electric relay,: the combination of an electrically energizedmagnetic field, a chamber of insulating material'defining an enclosedspace in said magnetic field, magnetic cores extending into the interiorof said chamber and spaced apart from each other, a plurality of ballscomposed of material having a low magnetic retentivity retained withinsaid chamber and normally occupying a. portion of the space between saidcores, said balls being adapted to be moved by the magnetomotive forceof said magnetic field to bridge the space between said terminals inmutually contacting relationship, and means for adjusting the relativeposition of said chamber with respect to said magnetic field.

2. In an electric relay, the combination of an electrically energizedmagnetic field, a chamber of insulating material defining an enclosedspace in said magnetic field, magnetic cores extending into the interiorof said chamber and spaced apart from each other, a plurality of ballscomposed of material having a low magnetic retentivity retained withinsaid chamber and normally occupying a portion of the space between saidcores, said balls being adapted to be moved by the magnetomotive forceof said magnetic field to bridge the space between said magnetic coresin mutually contacting relationship, and a duct through one of saidcores communicating with the interior of said chamber.

3. In an electric relay, the combination of an electrically energizedmagnetic field, a chamber of insulating material defining an enclosedspace in said magnetic field, magnetic cores extending into the interiorof said chamber and spaced apart from each other, and a plurality ofspherical elements composed of material of low magnetic retentivitydisposed within said chamber, one of said cores having an enlarged flatsurface, the other of said cores being in the form of a cylinder havinga. rounded end, whose axis is disposed normal to said fiat surface.

4. In an electric relay, the combination of an electrically energizedmagnetic field, a chamber of insulating material defining an enclosedspace in said magnetic field, magnetic cores extending into the interiorof said chamber and spaced apart from each other, and a pluralityofspherical elements composed of material of low magnetic retentivitydisposed within said chamber, one of said cores having an enlarged fiatsurface, the other of said cores being in the form of a cylinder havinga rounded end, whose axis is disposed normal to said flat surface and acoating of material having a relatively high co-eificient of electricconductivity on the contacting surfaces of said magnetic cores.

5. In an electric relay, the combination of an electrically energizedmagnetic field, a chamber of insulating material defining an enclosedspace in said magnetic field, magnetic cores extending into the interiorof said chamber and spaced apart from each other, a plurality ofspherical elements composed of material having a low magneticretentivity retained within said chamber and. normally occupying aportion of the space between said cores, one of said cores having anenlarged flat surface, the other of said cores being in the form of acylinder having a rounded end, whose axis is disposed normal to saidfiat surface and a coating of material having a relatively highcoefficient of electric conductivity on the contacting surfaces of saidcores, said particles also having a surface coating of material ofrelatively high electric conductivity.

-6. In an electric relay of the character described, the combination ofan electrically energized magnetic field, magnetic cores conducting saidfield and mounted in spaced relationship, and a plurality of relativelysmall balls composed of material having a low magnetic retentivity,

said balls being confined in a space between said cores, one of saidcores projecting into the midst of said balls when in normal positionand being surrounded thereby, said balls being adapted to bridge thespace between said cores upon energi- 5 zation of said magnetic field.

7. In an electric relay, the combination of an electrically energizedmagnetic field, a chamber of insulating material defining an enclosedspace in said magnetic field, magnetic cores extending into the interiorof said chamber and spaced apart from each other, a plurality of ballscomposed of material having a low magnetic retentivity retained withinsaid chamber and normally occupying a portion of the space between saidcores, one of said cores projecting into the midst of said balls when innormal position and being surrounded thereby, said balls being adaptedto be moved by the magnetomotive force of said magnetic field to bridgethe space between said cores in mutually contacting relationship.

8. In" an electric relay, the combination of an electrically energizedmagnetic field, spaced apart terminals within said field, and aplurality of spherical elements of magnetic material occupying a portionof the space between said terminals, one of said terminals having a flatsurface, the other having a cylindrical surface whose axis is disposednormal to said fiat surface.

9. In an electric relay, the combination of an electrically energizedmagnetic field, spaced apart terminals within said field, and aplurality of spherical elements of magnetic material occupying a portionof the space between said terminals, one of said terminals having a flatsurface, the other having a cylindrical surface whose axis is disposednormal to said flat surface, the diameter of said cylindrical surfacebeing substantially twice that of said spherical elements.

LOUIS E. RICHMOND.

